Depending on implementation details, a notification service may effectively provide a subscriber or group of subscribers with timely information. One relatively well-known notification service was originally referred to as the Emergency Broadcast System (EBS). The EBS was designed to inform the public of emergency situations and to make use of a broadcasting syndicate that included Amplitude Modulation (AM) radio, Frequency Modulation (FM) radio, and Television (TV) broadcast stations.
In recent years, the Emergency Alert System (EAS) has effectively replaced the EBS. In addition to the broadcasting organizations mentioned above, the EAS also includes cable companies providing broadcast video services. Participation in national EAS alerts is mandatory for these broadcasting entities. Participation in state and local area EAS alerts is voluntary.